The crushing weight of a bundle of disparate thoughts rolling into one hits him like a ton of bricks and as soon as he registers that Negan is indeed speaking even though he doesn't listen to the worlds themselves, Doc turns, swiftly, practically lunging at Negan and sending them both crashing onto the already brittle floor. His hat slides into the storage room they had come from and he clamps his hand over Negan's nose and mouth firmly.

"Don't breathe," he warns, voice low and deathly serious, pinning the other man down for a few seconds to make sure he's still, and listening. When Doc feels a nod or some kind of acknowledgement, he jerks his head towards the way they had come in from and tugs Negan back onto his feet before shoving him on out of there as quickly as they can go, back to the window where they can climb back out and breathe again.

He can't be sure if he's just gotten a man killed, but he doesn't want to think about it too much, at least until they're out of there.